High-tension magneto-electric machine.



W. 0. KENNINGTON.

HIGH TENSION MAGNETO ELECTRIC MACHINE.

APPLICATION FILED OUT. 10, 1911.

Patented Sept; 24, 1912.

iww In llll I!! I 5 is 85 fla [NI/EN TOR Allarneyo UNITED STATES PATENTOFFICE.

WILLIALT KENNINGTON, OF BLOOMFIELD, NEW JERSEY, ASSIGNOB TO SIMMSMAGNETO CO. INC., OF NEW YORK, N. Y., A CORPORATION OF NEW YORK..

HIGH-TENSION MAGNETIC-ELECTRIC MACHINE.

Specification of Letters Patent.

Application filed October 10, 1911. Serial No. 653,974.

T0 at! whom it may concern:

Be it known that I, VILLIAM O. IQEN N ING' ION, a subject of the King ofEngland, citizen of London, England, residing at Bloomfield, in thecounty of Essex and State of New Jersey, have invented certain new anduseful Improvements in High-Tension ltIagneto-Electric Machines; and Ido hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

My invention consists in the novel features hereinafter describedreference being had to the accompanying drawings which show one form .orembodiment of the invention which I have selected for purposes ofillustration, and the invention is fully disclosed in the followingdescription and claims.

The'object of my invention is to provide.

a high'tension magnet-0' electric machine, the armature of which has twomaximum or sparking positions in each .half revolution I complished bythe peculiar construction of neto electric machine embodying my invention, as is necessary for a clear understanding of my invent-ion. F ig.2 is a perspective view of one of the pole shoes detached.

In the drawing, 1 represents the magnets of the magneto, which ha etheir poles provided with the pole picces 2, '3, surrounding the rotaryarmature, the core of which is shown at 10 and which is pro ided withthe usual primary winding 11 and secondary winding 12, the windingsbeing-represented diagrammatically. Each pole piece is provided with anextended portion 2 at one end the other end being cut off andterminating in a vertically disposed face 2". Each of the pole pieces isprovided with a longitudinally extending angular recess .3 having avertically disposed face 3 and a horizontally disposed face 3*. Forconvenience in forming the pole shoe, I prefer to have the verticallydisposed face 3 in exact alincment, or. in the same vertically disposedplane as the face 2 at the other end of the pole piece, and the face 3perpendicular'to the face 3, whereby the faces 2", 3 and S -may beformed by a single cut of a suitable milling tool, but I do notlimitmyself to this exact construction.

The effect of the longitudinal grooves or recesses 3, is to provide twopoints in the revolution of the armature, where the greatest number oflines of force are cut by the coils of the armature, the one, as thecoils leave the adjacent edge of the faces 8*, and the other as theyleave the inner edge of the adjacent edge of the faces 3. It isalso'advantageous to arrange that of the two maxi mum positions, theretarded position will be best for low speed and the advance positionwill be best for high speed, and to acconr' plish this the trailing tipsof the extensions 2 of the pole shoe are cut off adjacent to each end ofthe shoe leaving inclined face-s4.

Patented Sept. 24, 191

This causes a greater reluctance to the flux I at full retard at a highspeed of the armature compared with the reluctance at full ad vance. Itfollows therefore, that withthe armature rotating at slow speed, withthe' circuit breaker or interrupter for the pri mary circuit at fullretard, the best spark will be produced, and in fact with this construction the spark so produced at slow speed is as hot as the sparkproduced when the magneto armature is rotating at full speed.

When the armature is rotated at high speed the spark is advanced, sothat the primary circuit is broken just before the coils leave the edgesof the faces 3 where the best spark is obtainednnder the conditions ofhigh speedf My improvement is adapted particularly to magneto electricmachines for use in connection with ignition devices for internalcombustion engines, especially those used in auromobilesand othervehicles, and it is obvious that in cranking the engine and in runningat slow speeds a full spark will be furnished for the ignition of theexplosive charges, in the cylinders, by throwing the timing lever of thecircuit breaker into the retarded position. I do not however, limitmyself toithe use of the invention for these purposes.

It willgbe understood that the magneto will be provided with the usualor anypreferred form of circuit breaker for the primary circuit,provided with means such as a timing lever, for advancing or retardingthe spark in the cycle of the armature and as these devices'are so wellunderstood, I have not considered it necessary to illustrate anyparticular form of circuit breaker or tiining'lever for this purpose. Imay, for example, employ the form of contact breaker and timing-leverused in the well known Simms high tension magneto electric machine, andshown for example in the British patent to Simms No. 1263 of W rat{claim and desire to secure by Letters .ldatcnt 1 l; In magneto electricmachine, the combination with the magnet thereof, c a pole shoe for themagnet having one extremity extended in direction around the armm tnrebeyond the other extremity, the inner face of said pole shoe beingprovided adjacent to the extended extremity thereof with a transverselyextending recess, to enablethe armature coils" to cut substantially thegreatest number of line's of force at two dif forent positions in eachrevolution thereof, while passing said 'shoe. e

2. in a magneto electric machine, the combination with the magnetthereof, of a pole shoe for the magnet having one extremity extended ina direction around the armature beyond the other extremity, the innerface of said pole shoe being provided adjacentto the extended extremitythereof with a transversely extending recess, to enable the armaturecoils to out substantially the greatest number of lines of force at twodifferent positions in each revolution thereof, and also with means forcausing a greater reluet-ance to the magneticfiux in one of saidpositions than in the :other.

3.- In a magneto electric machine,the combination with the magnetthereof, of a pole shoe for the magnet having one extremity extended ina direction around the armature beyond the other extremity, the innerface of said pole shoe being provided adjacent to the extended extremitythereof with a transversely extending recess, to enable the armaturecoils to cut substantially the greatest number of lines of force at twodiifercnt positions in each revolution thereof, portions of the extendedextremity of the pole shoe being cut away to cause a greater reluctanceto the magnetic flow at high speed.

4. In a magneto electric machine the combination' with the magnetthereof, of a pole shoe for said magnet having the extremity which islhst passed by the armature coils, during the rotation thereof extendedbeyond the other extremity of the shoe, and having a transverse recessin the inner'face of said shoe adjacent to the said extended extremitywhereby the armature will be given twb sparking positions. I

5. In a magneto electric machine the combination with the magnetthereof, of a pole shoe for said magnet having the extremity which islast passed by the armature coils, during the rotation thereof extendedbeyond the other extremity of the shoe, and having a transverse recessin the vinner face of said shoe, adjacent to the said extended extremitywherebythe armature will be given two sparking positions, the saidextended extremity of the shoe being of greatest length centrally of theshoe and diminishing in length toward each lateral end thereof, wherebya. greater reluctance to the magnet flux at one position is caused athigh speed, than at the otherposition,

6. A pole shoe for high tension magneto electric machines,having acurved inner face for embracing the armature, and having one endextended in a direction around the armature, to a greater extent thanthe other, said pole piece being provided .with a recess adjacent tosaid extended portion, said recess extending across the inner face ofthe pole shoe in a direction substantially parallel to the axis ofrotation of the armature.

7. A pole shoe for high tension magneto electric machines, having acurved inner-face for embracing the armature, and having one endextended in a direction around the armature, to a greater extent thanthe other, said pole piece being provided with a recess adjacent to saidextended portion, saidru extending across the inner face of the poleshoe in a direction substantially parallel to the axis of rotation ofthe'armature, the extremity of said extended port-ion beiiig cut away ateach end on'lines disposed angularly to the end face of said extendedportion.

8. A high tension magneto electric machine provided with a pole shoe,one end of which is provided with an extended portion, and havingadjacent thereto a longitudinal groove or recess provided with avertically disposed wall, in the plane of the outer face at the otherend "of the shoe, said recess having a longitudinally disposed face,disposed substantially perpendicularly tothe said vertically disposedwall.

9. A pole disk for high tension magneto electric machines provided Withan extended portion at one end, and having adjacent thereto alongitudinally disposed groove of recess provided with an innervertically d15- y m-1% wall in the plane of the outer face In testimonywhereofI affix my signature,

W tyne ether end of the shoe, and a horizonin the presence of twoWitnesses. huh diw pused all @uhstqntinlh' berpendicv 1 J ILI [AM 0. KENN INGTON. K1121 1' te the 'vertlvally dlsposed Wall, the sald W J 5extended pmtlon bemg cut away at each end Witnesses:

to term feces mchned to the extreme outer R GER H. BUTTERWORTH,

face thereof; JULIUS EHMANN.

